Effect of algae decaying on shrimp culture system and suggested biological remediation strategies

Abstract

Pond water with algae blooms was collected, and maintained in the dark over a 2-day period without nutritional supplements. The physico-chemical parameters and the density of algae were measured. The concentration of NH 4+-N, DIN and PO4--P in water in darkness significantly increased, and the density of algae decreased significantly. Isolated water was exposed to three bio-remediation water treatments: addition of green algae, Bacillus subtilis and photosynthetic bacteria. After remediation, the concentrations of NH4+-N, NO3- -N, DIN and PO4--P in the three treatment groups were significantly lower than the control group. No difference was observed in the concentration of NO2--N between the control group and the photosynthetic bacteria group. Results from all treatments showed water quality deterioration along with increase in nitrogen and phosphorus concentrations. Bio-remediation methods can be effectively adapted in shrimp culture after algae decay, and one of the most promising biological remediation strategies is the use of green algae.